A differentially pumped electron-energy-loss spectrometer with multichannel detector for time-resolved studies at intermediate ambient pressures

The design, construction, and operation of a high-resolution electron-energy-loss spectrometer featuring a position-sensitive resistive anode detector and differential pumping are described. The position-sensitive detector provides a 66-fold increase in acquisition speed over a single-channel spectrometer. The differential pumping provides pressure isolation of 105 between the spectrometer elements, except the lenses, and the sample region. An optically isolated multicomputer-based control and data acquisition system provides complete spectrometer control and automated sample cleaning and characterization. The spectrometer, together with a differentially pumped supersonic molecular beamline, permits in situ measurements of the interaction of a wide range of gas molecules with solid surfaces.